Apparatus for regulating the pressure at which air is blown into internal-combustion engines.



L.- T. EBERMANN. APPARATUS FOR REGULATING THE PRESSURE AT WHICH AIR IS, BLOWN INTO INTERNAL COMBUSTION ENGINES.

Patented July 1, 1913.

APPLICATION FILED FEB.27, 1913.

LUDWIG THAnnAUs EBERMANN, or AUGSHURG, GERMANY, AssIGNoR To MAscHI'NEN- FABRIK AUGSBURG-NTTRNBERG, AKTIEN A CORPORATION OF GERMANY.

essntrscnnrr, or AUGSBURG, GERMANY,

APPARATUS roa REGULATING THE rnnss'uia'n' Afr wares AIR is" BLOWN INTO INTERNAL-COMBUSTION ENGINES.

Specification of Letters Patent.

Patented July 1, 1913.

Application filed February 27,1913. Serial No. 751,179.

7 '0 all whom it may concern Be it known that I, LUDWIG THAD-DLiUs EBERMANN, a citizen of the Austro-Hungarian Empire, and residing at Augsburg, Germany, have invented certain new and useful Improvements in Apparatus for Regulating the Pressure at which Air is Blown into Internal-Combustion Engines, of which the following is a specification.

My invention relates to apparatus for regulating the pressure at which air is blown into internal combustion engines.

In internal combustion engines in which the air for combustion is separately compressed and the fuel afterward introduced into the highly compressed air by means of compressed injection air, particularly in those machines which run at a high and very variable speed, it has been found necessary to vary the pressure of the injection air corresponding to the speed and to the quantity of fuel requisite at any time. When'both the speed and the quantity of fuel suppliedare high, the injected air must 7 have a high pressure, when the speed is low this air must have a lower pressure, but when the quantityof fuel supplied is small both at a high and at a low speed, the pressure of the injected air must be correspondingly-lower. This must be brought about in such a way that when the speed is high and the quantities of fuel supplied are large (2'. e. at heavy loads), all the fuel is introduced into and properly sprayed in the cy1- inder in the very short time at disposal, but when the speed is low, high combustion pressures and shocks due to the fuel being introduced much too quickly mustbeavoided, and also when the quantity of fuel is small, those mi-sfires must be avoided which occur, as experience has proved, when the pressure of theinjection air is much too high, or the quantity of such air much too large. Methods of varying the pressure of the injection air by handor by automatic devices are known.

A primary object of my invention is to provide improved automatic apparatus for regulating the injection air in dependence on the speed and load of the engine; To this end I insert apressurewcducing valve in the injection pipe between the air-vessel supplying the injection air and the fuel valve. This pressure-reducing valve is influenced by the pressure of a liquid which is set in motion by a pump, said pressure varying, owing to the variation of the velocity of flow of the liquid, according to the hydraulic law of. outflowing liquids. To in fiuence regulating members by a pressure regulated according to the said hydraulic law is known per .96. In the present case special advantages are obtained :firstly, I am able in a specially simple manner to bring the pressure" of the injection air into two-fold dependence on the speedand on the load, and, secondly, I am able to make this dependence result according to a law,

which can be predetermined as desired, by

means of the addition of a device described hereinafter.

One embodiment of my invention is diagrammatically represented in sectional elevation by way of example in the accompany ing drawing which illustrates an apparatus for automatically regulating the pressure of the injection air in an internal combustion engine.

Referring to the drawing, I employ a balanced pressure reducing valve 6; which is not influenced in its action by the pressure in the vessel 0 which contains the injection air and is connected to said valve by the pipe b. In the first place, the pressure-reduei-n valve 6; is influenced on a projection d by t e pressure of a spring e which tends to hold the valve open. This pressure of the spring 6 is opposed by a pressure in the chamber f 01? the casing A of the pressure reducing valve which tends to close the valve a. The pressure of the spring e is so ad jfusted that the valve 0; allows that pres sure of injection air which is necessary when starting the engine. This is at the same time the lowest injection pressure which the valve a can adjust assuming that the air in the air-vessel 0 is always at a high pressure. The chamber f of the valve casing A. is directly connected by the in ect1onpipe 9 with the fuel-valve of the engine.

Now in order to,; .vary the pressure in the injection-pipe g'corresponding to the speed, e. e., to obtain at a high speed a high in ection pressure and at a low speed a low inthe engine, and is discharged through a valve 11 and a pipe is into a tank Z, from which it is lifted by the pump it through the pipe m. The valve i'is adjusted to a predetermined section of passage. Since the pump it delivers the same quantity each'revolution, the quantity delivered per second is proportional to the speed, and the'pressureof theliqfiid iii the pipe 12. varies with the quantity delivered per second according to the hydraulic law of the resistance and outflow of liquids, the section of passage through the valve 2' being constant. Consequently, the pressure p acting on-the piston (1 also varies, and thus the force tending to open the valve a, which is held balanced by a closing pressure of corresponding value in the chamber f. Therefore when the speed is high the pressure in the chamber 7 will be high in accordance with the high pressure of the liquid p, and when the speed is low the pressure in the chamberf will be low in accordance with the low pressure of the liquid.

In order to make the pressure in the inj ection-pipe 9 variable in accordance with the quantity of fuel or the load in such a manner that, at a given speed, the injection pressure may be less with a small quantity of fuel, i. e. a small load thanwith a large load, an additional valve 0 is provided which is connected with the regulating 'rod 12 of the fuel-pump or of the regulator, so that the valve 0, which at full load is closed or opened very little, opens a large section of passage at light loads or during idle running, through which 1 the liquid can flow away from the pipe at through the pipe'g into the tank. Consequently the pressure of the liquid in the pipe n diminishes owing'to liquid flowing away through the Valve 0 the liquid therefore exercises on the piston 03 or valve a a reduced pressure, whereby'the injection pressurein the chamber f and injection pipe g is reduced, 2'. e., ismade to vary accordingto the degree of admission in such a manner that when a large quantity of the engine.

of fuel is admitted, the pressure is high, while when a' small .quantity of. fuel is admitted, the pressure is low.

It is obvious that the two valves 2' and 0 could be united in a suitable manner.

Another method of making the pressure of the liquid in the pipe n, and consequently the injection pressure, dependent on the load consists in regulating the quantity of liquid.

delivered each revolution, by the pump it in correspondence with the required output In this case the valve 2' only will be'employed, it being fixedly adjusted to a predetermined section of passage.

Should the injection pressure need to be adjusted according to another law than one that corresponds to the law of hydraulic fiow'and resistance applicable to the valves z and 0, a slide valve 1' may be provided in a pipe 5 connected to the pipe n, which valve is loaded by the ressure of the liquid and counterbalanced y a spring t, and which valve when the pressure of the liquid-in creases, uncovers apertures and thereby causes said pressure to diminish, or on the other hand closes apertures in order to raise said pressure. The injection pressure may consequently be automatically raised or lowered as required.

I claim 1. A device for regulating the pressure of-combustion air, comprising a duct for the combustion air, said duct connecting with the fuel injection pipe of an internal com bustion engine; a regulating valve in said duct adapted to closethe inlet to the fuel injection pipe, a spring tending to open the valve and counteracting the pressure in the fuel injection pipe, means for automat-ically increasing the pressure on said regulating valve inthe direction to open,

sald increase of pressure depending on the increased speed of the engine.

2. A device for regulating the pressure of combustion air, comprising a duct-"for the combustion air, said duct connecting with the fuel injection pipe of an internal combustion engine; aregulating valve in said duct adapted to close the inlet to the fuel injection pipe, a spring tending to open the valve and counteracting the pressure in the fuel injection ipe, means for automatically increasing t epressure on said regulating valve in the direction to open, said increase of pressure depending onthe increased speed of the engine; said means comprising a charging pump driven by the engine, a conduit connecting said pump with said valve, a fluid supply pipe to said pump and a discharge pipe from said conduit, a manually operated discharge valve for openingsaid conduit into saiddischarge pipe.

3. A device for regulating the pressure of combustion air comprising a duct for the combustion air, said duct connecting with the fuel injection pipe of an internal combustion engine; a regulating valve in said .valve in the direction to open, said increase of pressure depending on the increased speed of the engine; said means comprising a charging pump driven by the engine, a

charge valve for opening said conduit into said dischar e pipe, said discharge valve actuated by t e governor ofthe engine.

4. A device for regulating the pressure of combustion air comprising a duct for the combustion air. said duct connecting with the fuel injection pipe of an internal combustionengine; a regulating valve in said duct adapted to close the inletto the fuel injection pipe, a spring tending to open the valve and counteracting the pressure in the fuel injection pipe, means for automatically increasing the pressure on said regulating valve in the direction to open, said increase of pressure depending on the increased speed of the engine; saidmeanscomprising a charging pump driven by the engine, a conduit connectin said pump with said valve, a fluid supp y'pipe to sald pump and a discharge'pipe from said conduit, a discharge valve for opening said conduit into said discharge pipe, aspring tending to .close said discharge valve'and a member for manually adjusting the spring pressure on said discharge valve.

5. A devicefor regulating the pressure of combustion air com rising a-duct for the combustion a1r, said duct connecting with the fuel injection pipe of an internal combustion engine; a regulating valve in said duct adapted to close the inlet to the fuel injection pipe,a spring tendlng to open A, the valve and counteracting the pressure in the fuel injection ipe, means for automatically increasing t e pressure .on said regulating valve in the direction to open, said increase of pressure depending on the increased speed of the engine, a member for manually adjusting the pressure of said spring, said means compr sing a charging pump driven by the engine, a, l' nduit connecting said pump with said regulating valve, a fluid supply pipe to said pump, and

a plurality of discharge pipes from said conduit, and a discharge valve opening said conduit into one of said discharge pipes, said discharge valve actuated by the governor of the engine, and an adjustable discharge valve for opening said conduit into another of said discharge pipes, a spring tending to close said adjustable discharge valve, and a member for manually adjusting the spring pressure on said adjustable discharge valve.

6. A device for regulating the pressure of combustion air comprising a duct for the combustion air, said duct connecting with the fuel injection pipe of an internal combustion engine; a regulating valve in said duct adapted to close the inlet to the fuel injectionpipe, a spring tending to open the valve and counteracting the pressure in the fuel injection pipe, means for automatically increasing the pressure on said regulating valve in the direction to open, said increase of pressure depending on the increased speed .suppy pipe to said pump, and a plurality of discharge p1pes from said conduit, and a discharge valve opening said conduit into one of said discharge pipes, said discharge valve actuated by the governor of the en gine, and an adjustable discharge valve for opening said conduit into another of said dischar e p1pes, a spring tending to close' said ad ustable discharge valve, and a member for manually adjusting the spring pressure on said adjustable discharge valve, and a manually operated discharge valve for opening said conduit into still another of said discharge pipes.

In testimony whereof, I aflix my signature in the presence of two witnesses.

LUDWIG THADDKUS EBERMANN. Witnesses:

RICHARD LEMP, JOHANNA STERN. 

